I Need A Bigger SSD And PCI-E Lanes Are Confusing Me

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I currently have 3 drives (2 SSDs, 1 HDD) crammed into a Node 202 on a B350 motherboard with a Ryzen 5 1500X. The two SSDs are fairly small, so I'm looking to finally populate my board's single M.2 slot with a 1 TB SSD, but the slim price difference between SATA and NVME M.2 drives has me all confused.

Looking around on Amazon right now, I can get a 1 TB Samsung 860 EVO SATA M.2 for about £125, or a 1 TB Crucial P1 NVME M.2 for about £1 less. I actually have both Crucial and Samsung brand SSDs in my system already, and while I've had less trouble with my Samsung, the theoretical gains of Crucial's NVME is throwing me off.

While I think most would say it's a no-brainer given the identical pricing, the sudden realization of PCI-E lane saturation is confusing me. I currently have a GTX 1060 3GB in my board's sole x16 slot, but I hear concerns that adding an NVME drive could cut into that lane allowance while going for the SATA M.2 could kill off my final unused 4th dedicated SATA socket. My board manual says the M.2 socket is "socket 3, M key, type 2260/2260/2280 SATA and PCIe x4 /x2 SSD)" and that the PCIe x4 part will "vary by CPU".

My other concern is that the Crucial P1 apparently thermal throttles at around 60 degrees. Given it'll be crammed into the Node 202 for a few more months before I'm able to switch back to a case with better airflow, I think there's a good chance that might become a problem given it won't have a fan pointed at it.

So the question is; which do I go for? I'd like to futureproof with an NVME given it's the same price, but I don't want to eat into the limited lanes I have for when it comes to upgrade my GPU.

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While I think most would say it's a no-brainer given the identical pricing, the sudden realization of PCI-E lane saturation is confusing me. I currently have a GTX 1060 3GB in my board's sole x16 slot, but I hear concerns that adding an NVME drive could cut into that lane allowance while going for the SATA M.2 could kill off my final unused 4th dedicated SATA socket. My board manual says the M.2 socket is "socket 3, M key, type 2260/2260/2280 SATA and PCIe x4 /x2 SSD)" and that the PCIe x4 part will "vary by CPU".

Ryzen CPUs, but not APUs (at least not all of them), come with 16 PCIe 3.0 lanes for GPU(s), 4 PCIe 3.0 lanes for an M.2 NVMe drive, and the connection to the chipset (which handles USB, networking etc. in addition to having some number of PCIe 2.0 lanes, depending on which chipset).

Those extra 4 PCIe 3.0 lanes for M.2 is why the motherboard manual says it will "vary by CPU." Since you've picked a Ryzen CPU that comes with those lanes, you have nothing to worry about.

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Ryzen CPUs, but not APUs (at least not all of them), come with 16 PCIe 3.0 lanes for GPU(s), 4 PCIe 3.0 lanes for an M.2 NVMe drive, and the connection to the chipset (which handles USB, networking etc. in addition to having some number of PCIe 2.0 lanes, depending on which chipset).

Those extra 4 PCIe 3.0 lanes for M.2 is why the motherboard manual says it will "vary by CPU." Since you've picked a Ryzen CPU that comes with those lanes, you have nothing to worry about.

That's the best answer I could have hoped for, thanks! So I guess that means the Crucial P1 is the clear choice here. Now I just have to work out the thermal issue. I had no idea M.2 drives got so toasty before looking into all this.

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That's the best answer I could have hoped for, thanks! So I guess that means the Crucial P1 is the clear choice here. Now I just have to work out the thermal issue. I had no idea M.2 drives got so toasty before looking into all this.

I suppose that's true. I know I'm not exactly the target audience for an NVME drive, but when they're so much faster at the same price in the particular instance, it's difficult to see why I'd get a traditional SATA M.2. I'm not even sure I'd bother migrating Windows to use it as a boot drive; I just need more space for games honestly - though I guess the standard SATA drives become the bottleneck when transferring currently installed games to the NVME, so I wouldn't even really push to those speeds then, huh?

I hear they make good content creation drives, though, and while I'm not exactly in that field right now, it would be nice to know I'm somewhat equipped for it should I find the inspiration to give it a shot. I only ever hear comparisons go in favor of SATA when there's a large price difference, but that's not the case here.